Squealing belts and hot oil !!

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tcook
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Squealing belts and hot oil !!

Post by tcook »

I contacted the forum a while back about a squealing drive belt on the HP pump on
my BX.
I made the time old mistake of selling the car to a friend of mine, and he is again having the problem. I must add that the reason I washed my hands of the car (finally) was that the clutch went, and the noise then stopped completely. I thought (wrongly) that the clutch slipping was the noise problem, and thought it would be OK to get rid of the car. My friend took the car on, and had the clutch adjusted so that it worked again, and the noise started again. My friend has since put a recon pump on after talking to my local garage, who admit they know sod all about Citroens, and that
still hasn't done a thing. The other problem is that the LHM fluid is
getting very hot, and the belts are getting very hot and shredding. I
changed the belt tensioner when I had the car in case the bearings were shot.
Can you suggest a reason as to why the oil is getting hot, I assume that the fluid is being held up somewhere under pressure. I also changed the regulator and accumulator when I owned the car.
Sorry this is all over the place, I am just trying to make sure I tell you all the facts.
Let me know what you think, I would love some input.
could it be the flow valve?
drop me a line!
(I'd love some input from AlanS in OZ, but his email won't work!)
Edited by - tcook on 29 Aug 2002 23:23:40
alan s
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Post by alan s »

Sorry about the e-mail...I'm having nightmares with it at the moment; one day it works, then it doesn't, then it does, and so on ad infinitum <img src=icon_smile_angry.gif border=0 align=middle>
These types of problems are always a bit of a hit & miss affair. My initial thought was pressure regulator and I still tend that way. Are you sure that this P/R is definitely not faulty? The reason I say this is that if the PR is leaking and fluid is going in & out like a fiddlers elbow, it's going to get hot. This LHM has only very limited lubricating properties, so much so that is it were put in an engine, I doubt it would see you to the end of the street, so any excessive working of parts will show up in the form of friction and hence heat. The PR was always a part that comes under suspicion on BXs; they didn't on CXs but due to being made different, were nowhere near as reliable on the BX.
Also remember; when the pump belt is adjusted, don't think like a fan belt or a water pump belt on other cars; think like Eric Clapton would when tuning his guitar! It has to be t i g h t. Any flexing and it will trash the belt, however, don't waste your money on a new belt just yet. If it's possible to get hold of another known good P/R, that's the way I think I would go.
Hope I have pointed you in the right direction but as I said at the outset; she's a bit of a hit & miss....but I feel I've got it right.
Alan S
Jon

Post by Jon »

Guys,
Alan will remember this from the Citroen Techinical forum. I had an almost identical problem on a colleague's BX, and it took a lot of head scratching, but I did solve it.You've just hit the nail on the head with this phrase from the original post<font color=red>"I assume that the fluid is being held up somewhere under pressure".</font id=red>
You're quite right, to stall the pump, throw the belt and heat up the LHM like this you've got an obstruction in the high pressure side of the system. I worked my way through the components and pipes on the high pressure side, pipe from pump, flow, regulator etc etc. What I found, when starting to remove the flow valve in order to replace it with a known good one to eliminate it from our enquiries was that whoever had replaced the flow valve sometime in the past had trapped the LHM seal where the high pressure pipe entered the flow valve so that the passage of LHM was obstructed. I fitted a new seal (put it on the pipe first), re-tightened the pipe nut, and all was well!
I'm sure that you have a similar problem here, and that your problem lies either in the flow valve or its piping.
Also work checking the metal pipe from the pump to the flow, sometimes it gets trapped between the engine and gearbox if the 'box has been out.
Jon Wood
IT Supervisor
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Dave Burns
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Post by Dave Burns »

Hmmm, I don't subscribe to the theory that the oil is going to heat up because there is resistance to the flow somewhere, after all it spends its entire life being forced through small openings at high pressure.
My thoughts are that there is resistance beyond the norm somewhere causing the belt to slip on the pump pulley and generate heat, this then traveling along the shaft into the pump and being carried away by the oil.
Or the pump is in big trouble and is generating the heat its self from internal friction.
where ever its being generated should be easey to identify by touch I would have thought.
Dave
alan s
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Post by alan s »

Dave,
If my memory serves me correctly, didn't someone recently post with a Xantia who had a very similar problem?
And didn't it turn out to be a faulty P/R that had caused damage to the pump? Or have I been drinking my own bath water again?<img src=icon_smile_wink.gif border=0 align=middle><img src=icon_smile_clown.gif border=0 align=middle>
It does happen at times you know<img src=icon_smile_tongue.gif border=0 align=middle>
Alan S<img src=icon_smile_big.gif border=0 align=middle>
Jon

Post by Jon »

Dave & Alan,
TCook says in his original post that the pump has already been replaced with a recon unit.Assuming that this pump checks out, why should it cause the same problems as the original ie slipping the belt and heating up the LHM?
This problem has got to lie with the regulator as Alan says, and I personally believe that the flow valve is also worthy of examination. The reason I say this is that the flow gets pump pressure before its diverted into the Reg. Also bear in mind that our man states he's already replaced the Reg and the accumulator, as well as the pump.
To me its got to be the flow, or some problem with the metalpipe from the flow to the pump.(I mention before that I've seen them crushed due to careless gearbox fitting).
I may be wrong, the above are my theories.
Otherwise 1) The regulator that was fitted is faulty 2) Theres a problem with the recon pump..... but?
Jon Wood
IT Supervisor
GSF t/as Andyspares
<font color=purple></font id=purple>
Edited by - Jon on 02 Sep 2002 10:31:59
alan s
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Post by alan s »

Jon,
I am not an exponent of the lightening striking twice theory, but under these circumstances, I think it's time to retrace the steps. After all, we're talking about a pump sucking a liquid, blowing it into a pressure regulator, a portion being syphoned off to mank the steering and the rest being used to make it stop (when required) and pump up the suspension. As you say, short of a squashed pipe, causing the pump to work overtime, the rest has to be viewed as a return of a potentially common problem not rectified due to a faulty reconditioned or second hand part that's been fitted.
I'm interested to see what it turns out to be.
Alan S
Dave Burns
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Post by Dave Burns »

Hi Jon, Alan, wether of not it's the regulator, FDV, pinion valve or a pinched pipe isn't in dispute, it's going to be one them for sure but this in its self wont heat up the oil, don't see how it could.
Doesn't matter what pressure the oil is at, it cant be compressed therefore couldn't produce heat.
It can as said earlier cause the belt to slip on the pump pulley, or overload the pump causing high friction of the internal's and generate the heat that way.
My dosh is on the FDV because the oil goes through it first on the way to the regulator or power steering, if the diagrames Iv'e seen on the hydraulic system are faithful that is, (some would appear not to be).
If the car hasn't got power steering then the money goes on the regulator cos then there aint no FDV, or are there two bathwater boozers on here<img src=icon_smile_big.gif border=0 align=middle><img src=icon_smile_tongue.gif border=0 align=middle><img src=icon_smile_big.gif border=0 align=middle>
Dave
alan s
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Post by alan s »

Dave,
I think this back & forth banter will eventually sort it<img src=icon_smile_wink.gif border=0 align=middle>
You gave me one clue with your last reply; I think I still have discounted the F/D due to the fact that we often get owners with the filters in these blocked but who don't get the symptoms described here. Another important point is that priorities dictate that brakes, then suspension and finally power assistance for the steering are the order, hence anything to do with the f/d is usually dramatic as far as the driver is concerned (tell me about it; I once snapped a belt on a 16 Trs as I entered a Hospital car park...nearly had to be admitted for a hernia operation<img src=icon_smile_sad.gif border=0 align=middle>
Something that may also come into the equation; when the new parts were fitted, were new high pessure line seals fitted and if so, were all of the ports checked that no old ones were left in? I'd like a quid for every time I've found a nicely green painted "O" ring stuck to the bottom of a sphere on a "redone" sphere. This or a wrongly fitted seal could possibly duplicate a blockage problem; worth a thought?
Alan S
P.S.
Found the other topic on a similar problem I spoke about earlier.
http://www.andyspares.com/discussionfor ... PIC_ID=746
Edited by - alans on 02 Sep 2002 23:49:23
Also, the previous posting referred to by the above lister mbunting. Posted it below so as to give all the details for comparison of the two cases.
http://www.andyspares.com/discussionfor ... PIC_ID=639
Edited by - alans on 03 Sep 2002 00:16:32
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